(i) Technical Field
The present invention relates to a light-emitting element, a self-scanning light-emitting element array, an optical writing head, and an image forming apparatus.
(ii) Related Art
Surface light-emitting element arrays are used in a writing head of a contact image sensor, a printer, and the like. A typical surface light-emitting element array is configured by integrating multiple light-emitting elements arranged in a linear form on one substrate. As typical examples of a surface light-emitting element, alight-emitting diode (LED), a light-emitting thyristor, and a laser diode are known. Among these examples, alight-emitting thyristor has a configuration in which compound semiconductor layers of GaAs or AlGaAs are stacked in a pnpn structure, and an electric current flows between an anode and a cathode when a driving current is applied to a gate, whereby the light-emitting thyristor emits light.